Impedance
Use the Impedance node in frequency domain analysis to define the specific (input) impedance of an external domain as the ratio of pressure to normal velocity Zn = p/(n · v), at the boundary. The formulation is following the so-called Ingard-Myers condition. The associated impedance boundary condition is
Impedance (Ingard-Myers)
Enter a Specific impedance Zn (SI unit: Pa·s/m).